This exploratory project is aimed at investigating the potential of newly developed optical interferometric technique that we developed- Spatial Light Interference Microscopy (SLIM)-- for characterizing blood smears and tissue biopsies. SLIM is label-free and uniquely sensitive to refractive index modifications brought to the biospecimen by disease development . If successful, in the long-run, i.e. 5-10 years period, we anticipate that this label-free approach to imaging biospecimens will provide faster access to clinically-relevant data, as it bypasses most of the histology preparation process, e.g. staining. Further, due to its exquisite sensitivity to structural changes in the tissue, SLIM will provide a greater wealth of information than common histology, which should aid the pathologist in reaching a faster, more accurate diagnosis. The exploratory stage project will have the following specific aims: develop advanced, high-throughput instrumentation, perform proof-of principle studies on blood smears with focus on several specific diseases, and image biopsies of normal and three types of cancers (breast, prostate, and lung).